1. Field of the Invention
The present invention relates to a hardening processing apparatus and method and a coating film forming apparatus each for forming a coating film such as an interlayer insulating film on a substrate such as, for example, a semiconductor wafer, an FPD substrate (flat panel display substrate), and so on.
2. Description of the Related Art
In manufacturing processes of a semiconductor device, there may be a case where an interlayer insulating film is formed by, for example, an SOD (Spin On Dielectric) system. In this SOD system, a coating material is applied by spin coating onto, for example, a semiconductor wafer (hereinafter, referred to as a “wafer”) and subsequently subjected to physical processing such as heating and chemical processing to form the interlayer insulating film. Specifically, in the case of using, for example, a coating solution composed of “Silk” (trade name) that is one of cyclobutene based polymer insulating film materials, the interlayer insulating film is formed by performing baking processing of heating at a temperature of, for example, about 320° C. for one minute for the wafer coated with the coating solution and then performing curing processing for about five minutes under the conditions of a temperature at about 450° C. and an oxygen concentration of 20 ppm or lower to harden the coating film.
As an apparatus for performing the curing processing, there is a proposed configuration which includes a processing chamber for heating wafers coated with a coating solution one by one and a cooling processing chamber for cooling the wafer which has been subjected to the heating processing and transferring a wafer to the processing chamber from the outside of the curing apparatus (see Japanese Patent Publication No. 2000-124206).In the processing chamber, predetermined curing processing is performed by mounting a wafer on a hot plate whose set temperature can be set to 200° C. to 470° C.
However, in the configuration disclosed in the published technology, a curing temperature of about 450° C. is required in the case of using the coating solution composed of “Silk” (trade name), but the processing performed at such a high temperature might adversely affect devices due to heat in the future when the pattern becomes finer.